icmp_prepend_hdr
static mblk_t *icmp_prepend_hdr(conn_t *, ip_xmit_attr_t *, const ip_pkt_t *,
mp = icmp_prepend_hdr(connp, ixa, ipp, &v6src, &v6dst, 0, mp, &error);
mp = icmp_prepend_hdr(connp, ixa, ipp, &v6src, &v6dst, flowinfo, mp,